The present invention relates to a portable crushing device for preparing aggregate and the like.
When developing a remote site such as a mine or quarry, it is necessary to provide or improve roadways either leading to the site or within the site itself. Such roadways are necessary to allow the equipment used ill developing the site to move freely and typically the roads are made from crushed rock that can be deposited, smoothed and compacted to provide a serviceable roadway.
However, the very remoteness of or poor access to the site may make it impractical to have a rock crusher conveniently located to produce the aggregate for making a roadway. Moreover, a conventional mobile rock crushing plant may be too large or heavy for use within the site until such time as the roads have been developed.
In most locations there is an ample supply of blasted stone available but it may be impractical or uneconomical to have a rock crusher located at the site. Even if a crusher is available, it is inconvenient to carry the blasted rock from the mine or quarry, crush it to a size suitable for building a road, and then transport it back to the mine for building a roadway.
In U.S. Pat. No. 4,441,415 there is taught a crusher adapted for crushing or flattening scrap metal and, particularly, auto body shells. The crusher is mounted on a tractor and includes a pair of crushing jaws. One of the jaws is stationary while the other is pivotally mounted with the pivot point positioned at the outlet of the crusher. The relative motion of the jaws is accomplished by means of hydraulic cylinders acting directly oil the moving jaw. This reference does not teach a crusher for aggregate material.
U.S. Pat. No. 3,959,897 teaches a rock crusher adapted for mounting on a dredging device. The crusher includes a pair of jaws, one being stationary and the other pivotally mounted and acted upon by a hydraulic cylinder. The pivot point for tile moving jaw is located near the outlet of the crusher and the cylinder acts through an eccentric shaft. It is therefore an object of the present invention to obviate or mitigate the above disadvantages.
In general terms, the present invention provides a portable crusher for attachment to a boom of an earthmoving vehicle. The crusher has a hopper with a material inlet and a material outlet spaced from the inlet. A pair of jaws is located within the hopper and positioned between the inlet and outlet. The jaws are movable relative to one another to vary the spacing therebetween and an actuator is provided to control relative movement between the jaws. Material moving from the inlet to the outlet thereby passes between the jaws and is crushed upon relative movement of the jaws to provide an aggregate at the outlet.
Preferably the actuator is a hydraulic actuator and one of the jaws is fixed while the other may pivot relative to the hopper under the control of the actuator.
It is also preferred that the jaws are biased apart and that the biasing is provided by a mechanical spring.
By providing a crusher that may be attached to the boom of an earthmoving vehicle, it is possible to transport the crusher prior to improvement of the roads to the location at which the raw materials are available for crushing into aggregate. Moreover, the feed of material between the inlet and outlet may be controlled by operation of the boom-leveling mechanism and the hopper may be utilized to transport the crushed material if convenient. Thus, the invention provides a portable crusher comprising:
a hopper having a material inlet and a material outlet spaced from the inlet;
a pair of jaws within the hopper positioned between the inlet and outlet, the jaws being moveable relative to one another, whereby material moving from the inlet to the outlet passes between the jaws and is crushed; and
an actuator to effect the relative movement between the jaws;
wherein the pair of jaws comprise a first, moveable jaw, connected to the actuator, and a second, stationary jaw, the first jaw having a first end at the inlet and a second end at the outlet;
the improvement comprising the first end of the first jaw being pivotally connected to the hopper and the second end of the first jaw being connected to the actuator.